Inside the room, a man was detained and while speaking to a woman identified as the defendant police observed what they believed to be drug activity and performed an emergent search, prosecutor Sergeant Kathy Stafford said.

They detected 0.58 grams of marijuana and 0.13 grams of a clear crystal substance that Whelan said was "ice" or "crystal meth".

Whelan told officers she bought the marijuana earlier that day.

She said she used marijuana to "come down" from the effects of ice, Sgt Stafford said.

Her and her boyfriend had bumped into a friend and she'd asked that friend if they could "get on", meaning score some marijuana, the Mackay Magistrates Court was told.

The friend returned later that day with the drugs.

Among the belongings strewn about the hotel room officers also found a pipe and a light bulb that had been turned into a makeshift utensil for smoking ice, the court was told.

Whelan was also caught possessing a drug utensil on August 13 and September 5.

She pleaded guilty to all charges.

Legal Aid Queensland duty solicitor Kristie Doyle said at the time of her offending Whelan was in a situation of homelessness and living a transient lifestyle. She had since been homed.

Whelan possessed the drugs for her own use and the supply charge was in relation to her giving drugs to her partner.

There was no commerciality, Ms Doyle said.

The teen accepted she made admission even though the search "was somewhat questionable", Ms Doyle said.

Whelan was placed in a $600 four-month good behaviour bond and must attend a drug assessment and education session.

She was also fined $600 and no convictions were recorded.

Acting Magistrate Scott Luxton warned her that if she continued with this type of behaviour it was inevitably result in her returning to court.